condensation prevention and controlHow to cope with condensation

Stafna Chapman, owner of Curedamp Ltd, a firm specialising in Barnsley damp proofing services provides professional guidance and observations on the cuases of condensation in old houses and how to avoid them

Condensation is distinct from other types of dampness, such as rain penetration and rising damp. It’s water released when air is cooled to its dewpoint temperature and unable to carry so much moisture as vapour – the opposite process to evaporation.

This could occur indoors when warm, damp air comes into contact with colder building components. It may lead to mould and timber decay. However, a few simple measures may successfully reinstate the delicate moisture balance in old properties to stop condensation.

What causes condensation?

Condensation can occur when more moisture is produced – typically from cooking or washing. Insufficient ventilation is a second cause, for example, because of double-glazing, blocking of flues and air bricks, or erroneous installation of roofing underlay.

Condensation happens largely in winter and might first be noticed when water droplets form on hard surfaces, or mould appears on absorbent finishes.

What is known as ‘interstitial’ condensation occurs inside building materials and elements. For instance, if a wall is covered with an impermeable barrier or renders that doesn’t allow moisture to move through the wall naturally.

How to stop condensation

In household buildings, simple change in lifestyle which lower humidity and/or keep surface temperatures above dewpoint typically provide a more practical and inexpensive long-term solution than dehumidifiers or whole-house ventilation systems.

Generate less moisture

Place lids on pans when cooking
Dry clothes out-of-doors
Close bathroom and kitchen doors when in use
Vent tumble driers to the outside if not of the condenser type

Improving ventilation

Open windows and avoid draughtproofing those in bathrooms and kitchens.
Ensure that lofts, floor voids and redundant chimneys are well ventilated and stay away from foam treatments on the underside of rooftops which can cause lumber decay.

Increased heating can maintain surfaces above dewpoint, particularly when run continuously at a low-level instead of intermittently. Lagging cold pipes may prevent surface condensation, as can enhanced insulation levels.

The video below from Wise Property Care explains in detail the causes of and prevention of condensation: